cosskill

cosskill is an AI communication simulator for rehearsing high-stakes conversations — salary negotiations, performance feedback, difficult personal talks — by speaking with realistic AI personas before they happen. 20 personas across operators, strategists, philosophers, and psychologists, mission mode with live meters, and conversation evaluations with a rewind so you can redo the hardest moment. Free to try: 3 messages without an account, 10 after sign-in. Pro is $12.90/mo or $129/yr unlimited. Built with Next.js/TypeScript.

Latest updates

7 October 2026

Neo • 7 Oct 2026solo founder

cosskill update: full Chinese-language interface is live — every persona & scenario works in EN and zh. Free: 3 messages without sign-up, 10 after sign-in; Pro $12.90/mo. Rehearse negotiations & hard talks with realistic AI personas → https://cosskill.com#cosskill

30 September 2026

Neo • 30 Sep 2026solo founder

New founder post: "Rehearse the conversations you dread" — what building an AI practice simulator taught me. Rehearsal beats research, second attempts matter, say it out loud. Rehearse raises, feedback, hard talks at https://cosskill.com#cosskill